A5191HRT AMIS HART™ Modem
1.0 Features
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Can be used in designs presently using the SYM20C15
Single-chip, half-duplex 1200 bits per second FSK modem
Bell 202 shift frequencies of 1200Hz and 2200Hz
3.3V - 5.0V power supply
Transmit-signal wave shaping
Receive band-pass filter
Low power: optimal for intrinsically safe applications
CMOS compatible
Internal oscillator requires 460.8kHz crystal or ceramic resonator
Meets HART physical layer requirements
Industrial temperature range of -40°C to +85°C
Available in 28-pin PLCC and 32-pin LQFP packages
Data Sheet
2.0 Description
The A5191HRT is a single-chip, CMOS modem for use in highway addressable remote transducer (HART) field instruments and masters. The modem and
a few external passive components provide all of the functions needed to satisfy HART physical layer requirements including modulation, demodulation,
receive filtering, carrier detect, and transmit-signal shaping. The A5191HRT is pin-compatible with the SYM20C15. See the Pin Description and Functional
Description sections for details on pin compatibility with the SYM20C15.
The A5191HRT uses phase continuous frequency shift keying (FSK) at 1200 bits per second. To conserve power the receive circuits are disabled during
transmit operations and vice versa. This provides the half-duplex operation used in HART communications.
Figure 1: 28-Pin PLCC Pinout Diagrams (green & non-green)
Figure 2: 32-Pin LQFP Pinout Diagrams (green & non-green)
AMI Semiconductor - Rev. 2.0, Mar. 05
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AMI [ AMI SEMICONDUCTOR ]
